JP2514134B2 - Buried object position exploration device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buried object position searching apparatus for searching a buried object position such as the earth or concrete by the time from electromagnetic radiation to reception of a reflected wave.

[0002]

2. Description of the Related Art As shown in FIG. 4, a conventional buried object position detecting apparatus receives a reflected wave of an electromagnetic wave radiated from a transmitting antenna 2 which receives an output from a transmitting / receiving circuit 4 toward a ground or a structure, and a receiving antenna 3 The signal is received by the transmission / reception circuit 4 via.
When the transmission / reception circuit 4 starts transmission, the address counter 11, which will be described later, is cleared, the clock oscillator 5 and the display device 12 are subsequently driven, and the oscillation clock pulse from the clock oscillator 5 is used as a sampling pulse by the sample and hold circuit 6. The sample and hold is performed from the start, the variable attenuator 7 composed of a multiplier is input and attenuated, and the output of the variable attenuator 7 is supplied to the display device 12 for display.

During the time from the start of transmission to the reception of the reflected signal from the buried object in the transmission / reception circuit 4, the display device 12 performs baseline display from the start of transmission and displays the reflected wave. The reception signal is output from the transmission / reception circuit 4 when received, the reception signal is sampled and held by the sample hold circuit 6, the level is attenuated by the variable attenuator 7, and the reception signal is displayed on the display device 12. Therefore, at the start of transmission, that is, the baseline length from the baseline display start position until the reception signal is displayed, that is, the delay time from the transmission start to the reception of the reflected wave, the embedded object position is detected.

By the way, since the level of the reflected wave due to the buried object located deep from the ground is small, the gain of the transmitting / receiving circuit 4 is increased. However, since the level of the reflected wave from the buried object located shallow from the ground is large and the gain of the transmitting / receiving circuit 4 is large, the received signal of the reflected wave from the buried object located shallow to the ground is displayed as it is. When it is displayed on 12, the display scales over. For this reason, the buried object position detecting device is further provided with an attenuation amount control circuit 8 and the attenuation amount control circuit 8 is provided.
The attenuation amount control of the variable attenuator 7 is performed based on the output of the.

The attenuation amount control circuit 8 includes a memory 10 storing attenuation amount data as attenuation amount information and a clock oscillator 5.
Of the D / A conversion output, which is composed of an address counter 11 that counts the oscillation clock pulses of 10 to specify the address of the memory 10 and a D / A converter 9 that converts the data read from the memory 10 into an analog signal. Is supplied to the variable attenuator 7 as a variable attenuator, and the analog-converted signal obtained by converting the attenuation amount data read from the address of the memory 10 designated by the address counter 11 and the sample hold output are variable attenuators. 7, the sample and hold output is attenuated by the attenuation amount corresponding to the attenuation amount data, and the attenuated output is displayed on the display device 1.
2 is displayed.

[0006]

However, the attenuation amount information stored in the memory is fixed and different attenuation amount information which is different from each other and corresponds to the position from the surface of the ground or the structure, and the address of each of them is different. It is stored in.
Since the attenuation amount in the variable attenuator is controlled based on the stored attenuation amount information, there is a problem that it may be difficult to search the buried object in a place where the attenuation amount information is not suitable. .

Further, there is a problem that it is impossible to emphasize the position of the buried object by reducing the amount of attenuation around the buried object.

It is an object of the present invention to provide a buried object position exploring device which does not make it difficult to search a buried object and can emphasize the surroundings of the buried object position.

[0009]

A buried object position detecting apparatus according to the present invention comprises a receiving means for receiving a reflected wave of an electromagnetic wave radiated toward a ground or a structure, and a sample for holding a received signal from the receiving means. A hold circuit, an attenuation amount storage means for storing a plurality of pieces of attenuation amount information corresponding to the position of the buried object, and a variable for attenuating the sample-held signal by an attenuation amount corresponding to the attenuation amount information sequentially read from the attenuation amount storage means. Attenuator, display means for displaying output from variable attenuator, and scale of depth vs. attenuation amount and attenuation amount setting on display means when updating stored attenuation amount information of attenuation amount storage means
Cursor position for and display the cursor
And a means for updating the stored attenuation amount information to the attenuation amount based on the position of the electromagnetic wave, and searching the position of the buried object based on the time from the emission of the electromagnetic wave to the reception of the reflected wave. To do.

[0010]

According to the buried object position detecting apparatus of the present invention, the reflected wave of the electromagnetic wave radiated toward the ground or the structure is received by the receiving means, and the received signal from the receiving means is sample-held by the sample-hold circuit. The sample-and-hold signal is attenuated by the variable attenuator by the attenuation amount corresponding to the attenuation amount information sequentially read from the attenuation amount storage means, and the output of the variable attenuator is displayed on the display means, and when the electromagnetic wave is emitted. The position of the buried object is searched based on the time from when the reflected wave is received. If the attenuation amount information is not suitable for the burial location, the updating unit can update the stored attenuation amount information in the attenuation amount storage unit to the attenuation amount information suitable for the location.
The problem that the search for buried objects becomes difficult depending on the location will be solved.

Furthermore, by setting a small amount of attenuation around the buried object when updating the amount of attenuation, it is possible to emphasize the position of the buried object.

[0012]

EXAMPLES The present invention will be described below with reference to examples.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

In the present embodiment, the same components as those of the conventional example are designated by the same reference numerals, and duplicate explanations are omitted.

In the buried object position searching apparatus of this embodiment, the conventional buried object searching apparatus is further provided with an attenuation amount setting circuit 13 for updating the attenuation amount data in the memory 10. The attenuation amount setting circuit 13 has a built-in ROM storing a program and a RAM having a work area, and a graduation display function for displaying a graduation having a coordinate axis as an attenuation amount (dB) and a depth (m) on the display device 12. The CPU 14 has a cursor position information reading function for reading the cursor position with reference to the display scale and an address increment function, and a keyboard 15 having an attenuation amount update instruction key, a cursor key and an execution key.

The operation of the buried object position exploring apparatus of this embodiment constructed as described above will be described.

The transmission output from the transmission / reception circuit 4 is radiated as electromagnetic waves toward the ground or the structure through the transmission antenna 2. Address counter 11 based on the transmission output
Is cleared, and then the clock oscillator 5 and the display device 12 are driven.

The clock pulse output from the clock oscillator 5 is supplied to the sample hold circuit 6 as a sampling pulse, and the output signal from the transmitting / receiving circuit 4 is sampled and held in the sample hold circuit 6. At the time of transmission, the transmission / reception circuit 4 to the sample hold circuit 6
There is no output to the variable attenuator 7 regardless of the output of the D / A converter 9.
Is zero level, and the base line is displayed on the display device 12 from the start of transmission by the transmission / reception circuit 4.

The transmission / reception circuit 4 which receives the reflected wave of the radiated electromagnetic wave from the buried object outputs a received signal. The received signal is sampled and held by the sample and hold circuit 6 and output to the variable attenuator 7. Here, the sample-hold circuit 6 performs sample-holding when the received signal frequency is
This is because the frequency is 00 MHz, which is a high frequency, and is converted to a frequency of several tens of kHz that is easy to process by sample hold. The received signal and the sampled and held signal are as shown in FIG. In FIG. 2, the time from the emission of the electromagnetic wave to the generation of the reception signal corresponds to the position of the buried object, that is, the depth.

On the other hand, the memory 10 stores attenuation amount data according to the depth from the ground or the surface of the structure, and the address of the memory 10 is designated by the address counter 11 which counts the clock pulse, and the data is sequentially specified. The attenuation amount data corresponding to the deep position is read. Memory 10
The attenuation amount data read from is converted into an analog signal by the D / A converter 9, multiplied by the output from the sample hold circuit 6, and attenuated by the attenuation amount corresponding to the attenuation amount data. It goes without saying that this attenuation amount corresponds to the attenuation amount data stored in the memory 10.

However, since the address counter 11 counts the clock pulses output from the clock oscillator 5 driven at the same time as the start of transmission, the memory 10 is attenuated according to the depth from the ground or the surface of the structure. Since the amount data is stored, the attenuation amount data corresponding to the depth position of the buried object is read out when the reflected wave is input.

The output of the sample hold circuit attenuated in the variable attenuator 7 is supplied to the display device 12 and displayed. As a result, the level of the reflected wave due to the buried object located deep from the ground is small, but the gain of the transmission / reception circuit 4 is large, and the amount of attenuation in the variable attenuator 7 is small, so that the display device 12 is sufficiently displayed. It is at a certain level. On the other hand, although the level of the reflected wave due to the buried object located shallow from the ground is large and the gain of the transmission / reception circuit 4 is large, the amount of attenuation in the variable attenuator 7 is large, so that it is attenuated and displayed on the display device 12. When you do this, the display will not overscale.

However, since the attenuation amount information stored in the memory 10 is not suitable, when the attenuation amount information stored in the memory 10 is desired to be updated, the attenuation amount update instruction key of the keyboard 15 is pressed. Pressing the attenuation amount update instruction key causes the display device 12 to display the scale shown in FIG. 3 under the control of the CPU 14.

By operating the cursor key of the keyboard 15, the cursor position is moved to the update desired attenuation amount position at the position of zero depth on the scale display surface of the display device 12, and the cursor position is moved to the desired attenuation amount position. When moved, the execution key of the keyboard 15 is pressed. When the execution key is pressed, the attenuation amount information for the cursor position is read and converted into attenuation amount data, and the calculated attenuation amount data is stored in the address corresponding to the depth of zero of the memory 10. +1 is added.

Next, the cursor is moved to the desired attenuation amount position for the next address and the execution key is pressed to update the attenuation amount data of the next address. Similarly, the attenuation data of the next address is updated in the same manner. By the end of this update, all the stored attenuation amount data in the memory 10 is updated, and the attenuation amount data suitable for the search location is stored in the memory 10.

In the same manner as described above, when updating the attenuation amount, the attenuation amount around the buried object is set to be small and updated, so that the periphery of the buried object position can be emphasized.

[0027]

As described above, according to the present invention, since the attenuation amount storage means is provided with the updating means for updating the attenuation amount information stored in the buried object position detecting device, the attenuation amount stored in the attenuation amount storage means. When the information is not appropriate, the attenuation amount information suitable for the exploration location can be updated to the attenuation amount information, and it is possible to eliminate the difficulty of exploring the buried object.

When updating the attenuation amount, the display means decreases the depth.
Display of attenuation scale and cursor position for attenuation setting
And store the attenuation amount based on the set cursor position
Since the attenuation amount information is updated, the attenuation amount setting is
Easy to set. In addition, by selecting the amount of renewal attenuation, there is an effect that the surroundings of the buried object can be emphasized.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a waveform diagram of an input signal and an output signal of the sample hold circuit according to the embodiment of the present invention.

FIG. 3 is a diagram showing a display example for explaining updating of memory storage contents in an embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

 2 ... Transmission antenna 3 ... Reception antenna 4 ... Transmission / reception circuit 5 ... Clock oscillator 6 ... Sample hold circuit 7 ... Variable attenuator 8 ... Attenuation control circuit 9 ... D / A converter 10 ... Memory 11 ... Address counter 12 ... Display device 13 ... Attenuation setting circuit 14 ... CPU 15 ... Keyboard

Claims (1)

(57) [Claims] 1. A receiving means for receiving a reflected wave of an electromagnetic wave radiated toward a ground or a structure, a sample and hold circuit for sampling and holding a received signal from the receiving means, and a plurality of attenuation amounts corresponding to positions of buried objects. Attenuation amount storage means for storing information, a variable attenuator for attenuating the sampled and held signal by an attenuation amount corresponding to the attenuation amount information sequentially read from the attenuation amount storage means, and a display for displaying the output from the variable attenuator Means and the scale of the attenuation amount and the attenuation amount on the display device when updating the attenuation information stored in the attenuation amount storage device.
Display the cursor position for setting and
Update the stored attenuation amount information to the attenuation amount based on the
And a renewal means for searching the position of the buried object based on the time from the emission of the electromagnetic wave to the reception of the reflected wave.